I just learned about the euclidian algorithm and I just found the GDC of two numbers who wouldn't even fit in a tweet by themselves. I love maths. Sometimes at least.
Number A: 6356372573398355905784117280315958941162201214457687353072218974680676050037202607702752216400208489143886881457797584992998367155290159347219234599717639663488515797097375842868890162575871569010871571325007323372604352908268836033893706024835911437969901698346289063198197944854469609844412210580170
Number B: 1372417939661784197013446438879133646209553340498692559434301171373595750359814983562189460859256366679520391067590624664448344438757526209106834779559635423685884995033499276511205638028822532170117561329681753415281376547966596089138486673063796867868941414275928086898187742381661513930231618160285
GCD: 5
And yes, I could totally just guess that by looking at the numbers but instead I just have a few lines of elixir do the work (without having the chance of a bigger GDC). https://hastebin.com/inobumiyow.ex